package com.zwd.cases.demo.utilstest;

class Solution {
    public boolean isUnique(String astr) {
        int len = astr.length();
        for (int i = 0; i < len; i++) {
            for (int j = i+1; j < len; j++) {
                if (astr.charAt(i)==astr.charAt(j)) {
                    return false;
                }
            }
        }
        return true;
    }
}

class mainClass {
    public static void main(String[] args) {
        Solution solution = new Solution();
        boolean str = solution.isUnique("zwdd");
        System.out.println(str);
    }
}
